A taxonomic study of the genus Cheilosporum found along the Brazilian coast is presented. Two species were found: C. cultratum (Harvey) Areschoug and C. sagittatum (Lamouroux) Areschoug. This is the first record of C. cultratum for Brazil since 1870 by Martens. C. cultratum is restricted to the Cabo Frio upwelling zone in the state of Rio de Janeiro, Buzios and Arraial do Cabo, whereas C. sagittatum has a wider distribution along the southern and southeastern coast. Female/carposporangial conceptacles and early post-fertilization stages are described for the first time for C. sagittatum. Epithelial cells and Corallina-type trichocytes observed with SEM reveal additional characteristics potentially useful in separating Cheilosporum from other genera in the Janieae tribe. Descriptions, illustrations, geographic distributions, and comments concerning the taxa studied are also presented. The taxonomic position of Cheilosporum species previously reported for Brazil are also clarified.
Cheilosporum; Corallinales; geniculate coralline algae; Rhodophyta; taxonomy
